CVE-2026-47264 Discourse: Don't leak restricted tag group names via tag info
Unauthenticated users can view restricted tag group names if the tags_listed_by_group setting is enabled, exposing internal categorization data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47264?
CVE-2026-47264 is a medium-severity vulnerability in Discourse Discourse, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.4, 2026.3.0-latest to before 2026.3.1, and 2026.4.0-latest to before 2026.4.1, DetailedTagSerializer#tag_group_names returned every tag group a tag belonged to without filtering against the requesting user's visibility. With SiteSetting.tags_listed_by_group enabled, anonymous and unprivileged users hitting TagsController#info (which is exempt from requires_login) could read the names of tag groups restricted to specific user groups or non-visible categories. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.
Weakness: CWE-200
Which versions are affected by CVE-2026-47264?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | From 2026.1.0 | 2026.1.4, 2026.3.1, 2026.4.1 |
Products include Discourse Discourse.
How do I fix CVE-2026-47264?
Upgrade discourse to a fixed version for your release line: 2026.1.4, 2026.3.1 or 2026.4.1.
Is CVE-2026-47264 being exploited?
There is no known exploitation of CVE-2026-47264 in the wild and no public exploit code.
Other vulnerabilities in Discourse Discourse
- CVE-2021-41163 RCE via malicious SNS subscription payload
- CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file
- CVE-2022-39356 Discourse user account takeover via email and invite link
- CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes
- CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint
Sources
Also known as BIT-discourse-2026-47264, GHSA-4q5q-6hh6-53x2.